The invention relates to an apparatus for the conditioning of oily seeds, in particular soya beans, which have previously been crushed and which after conditioning are to be flocculated.
In a method for processing soya beans, the latter are firstly crushed on grooved rolls in a processing stage, i.e. they are prepared into crushed bean material. Here the aim is to obtain 2 to 8 sub-particles from one bean, and to hereby produce the least possible proportion of fine particles. After crushing, the crushed beans pass through a conditioning stage, the aim of this conditioning stage, amongst other considerations, is to lower the viscosity of the oil enclosed in the cells by raising the bean temperature to 55.degree. to 75.degree. C. In addition, particular stress is laid on the homogeneous heating of the bean particles of the crushed material, so that the originally rather more hard crushed bean material becomes uniformly plastic and in the subsequent flocculation on smooth roll mills is such that on being rolled out forms stable flakes approximately 0.3 mm thin, in situ. At the same time, depending on the intial conditions, additional drying may be carried out. In any case, any surface humidity arising through heating should be dried away, otherwise after the flocculating rolls or during extraction, caking and agglomerations of the flakes occurs which causes transportation problems in conveying devices and percolation problems in the extractor.
In the methods conventional to date, usually steam tube apparatus, and more rarely plate apparatus, are used for the conditioning stage. Both types of apparatus have a relatively large reaction volume. This is due to the poor heat transfer between tubes or plates and the large heat transfer surfaces therefore required for heating. The product is fed mechanically through the apparatus. The large dimensions of these apparatus (20 m long) automatically result in a period of dwell of approximately 20 minutes, which has led the trade to regard this time as physically necessary for good conditioning. The mechanical transportation through the apparatus, on the other hand, can cause the product to be damaged and to be treated unhomogeneously. This unhomogeneous treatment can be improved by an extension of the period of dwell, which in turn led the trade to demand the apparatus to be designed with a long period of dwell.
Nevertheless, the results of the conditioning in these known apparatus, which are expensive in terms of construction and energy and which occupy a large amount of space, are not always satisfactory.
Despite the long period of dwell, not all the particles are homogeneously plastic and accordingly able to be well flocculated. A proportion remains or becomes brittle and is damaged by friction. The particles, at least partially, also have surface humidity. Owing to the long processing time, both the oily components and the components containing protein in the material which is to be treated are affected.
Owing to the poorly conditioned material, the subsequent flocculation mills are also affected. The partially hard material intially requires greater force in order to be rolled flat into flakes, which increases the expenditure in energy and in maintenance.